chr12-51768971-G-A

Position:

chr12-51768971-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_014191.4(SCN8A):c.3008G>A(p.Arg1003His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,602 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

SCN8A
NM_014191.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 10.0

Variant links:

Genes affected

SCN8A (HGNC:10596): (sodium voltage-gated channel alpha subunit 8) This gene encodes a member of the sodium channel alpha subunit gene family. The encoded protein forms the ion pore region of the voltage-gated sodium channel. This protein is essential for the rapid membrane depolarization that occurs during the formation of the action potential in excitable neurons. Mutations in this gene are associated with cognitive disability, pancerebellar atrophy and ataxia. Alternate splicing results in multiple transcript variants.[provided by RefSeq, May 2010]

SCN8A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1

In a repeat II (size 272) in uniprot entity SCN8A_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_014191.4

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SCN8A. . Gene score misZ 0.78755 (greater than the threshold 3.09). Trascript score misZ 10.278 (greater than threshold 3.09). GenCC has associacion of gene with myoclonus, familial, 2, infantile convulsions and choreoathetosis, cognitive impairment with or without cerebellar ataxia, undetermined early-onset epileptic encephalopathy, complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 13, benign familial infantile epilepsy, seizures, benign familial infantile, 5.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.97

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
SCN8A	NM_001330260.2 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/27	ENST00000627620.5	NP_001317189.1
SCN8A	NM_014191.4 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/27	ENST00000354534.11	NP_055006.1
SCN8A	NM_001177984.3 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/26		NP_001171455.1
SCN8A	NM_001369788.1 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/26		NP_001356717.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN8A	ENST00000354534.11 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/27	1	NM_014191.4	ENSP00000346534	P4	Q9UQD0-1
SCN8A	ENST00000627620.5 linkuse as main transcript	c.3008G>A	p.Arg1003His	missense_variant	17/27	5	NM_001330260.2	ENSP00000487583	A1	Q9UQD0-2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152224

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000402

AC:

AN:

248822

Hom.:

AF XY:

0.00

AC XY:

AN XY:

134978

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000887

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1461378

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726900

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.00e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152224

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.00000826

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Early infantile epileptic encephalopathy with suppression bursts

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 01, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 406258). This variant has not been reported in the literature in individuals affected with SCN8A-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 1003 of the SCN8A protein (p.Arg1003His). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.82

BayesDel_addAF

Pathogenic

0.40

BayesDel_noAF

Pathogenic

0.33

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.86

D;.;.;.;.

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.94

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.99

D;D;.;D;D

M_CAP

Pathogenic

0.72

MetaRNN

Pathogenic

0.97

D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

4.4

H;H;H;.;H

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.82

PROVEAN

Pathogenic

-4.8

D;D;D;.;.

REVEL

Pathogenic

0.86

Sift

Pathogenic

0.0

D;D;D;.;.

Sift4G

Uncertain

0.011

D;D;D;D;D

Polyphen

1.0

D;.;.;.;.

Vest4

0.66

MutPred

0.85

Loss of MoRF binding (P = 0.0259);Loss of MoRF binding (P = 0.0259);Loss of MoRF binding (P = 0.0259);.;Loss of MoRF binding (P = 0.0259);

MVP

0.98

MPC

2.5

ClinPred

1.0

GERP RS

4.7

Varity_R

0.85

gMVP

0.98

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over